Verses 1–11
Moreover
In 2Cor. 8., 9., the apostle sums up the Christian doctrine of giving. It may be thus summarized:
(1) It is a "grace," i.e. a disposition created by the Spirit 2 Corinthians 8:7 (2) In contrast with the law, which imposed giving as a divine requirement, Christian giving is voluntary, and a test of sincerity and love 2 Corinthians 8:8-12; 9:1,2,5,7 (3) The privilege is universal, belonging, according to ability, to rich and poor 2 Corinthians 8:1-3,12-15; 1 Corinthians 16:1,2. (4) Giving is to be proportioned to income 2 Corinthians 8:12-14; 1 Corinthians 16:2. The O.T. proportion was the tithe, a proportion which antedates the law Genesis 14:20. (5) The rewards of Christian giving are (a) joy 2 Corinthians 8:2 (b) increased ability to give in proportion to that which has been already given 2 Corinthians 9:7-11 (c) increased thankfulness to God 2 Corinthians 9:12 (d) God and the Gospel glorified 2 Corinthians 9:13,14.
Verses 12–24
willing
See 2 Corinthians 8:10-12, (See Scofield "2 Corinthians 8:1").